Learn the Grammar from Song

If I Needed Someone

By: The Beatles

If I needed someone to love

You're tho one that I'd be thinking of

If I needed someone

If I had some more time to spend

Then I guess I'd be with you my friend

If I needed someone

Had you come other day

Then it might not had been like this

but you see now I'm too much in love

Carve your number on my wall

Then maybe you will get a call from me

If I needed someone 

We can learn the use of "if" and how to omit it (Conditional Sentence)

"If I needed someone to love"

- the sentence tells us about the untrue situation in the present. It's a normal category of conditional sentence.

"Had you come other day"

- the other type of conditional sentence. It is similar with the sentence "If you come some other day".